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(2020)Constant increase in protein consumption is global trend and can be seen in consumer behavior of Finnish markets. Consumers are interested in replacing meat proteins with plant proteins, and therefore, it is important to develop locally grown-domestic products and invest in local crop research. Due to this, the current study focuses on the domestic vegetable protein (faba bean and oat) texturing by extrusion cooking and on their functionality when included in burgers. The literature section presents an overview of previous studies on extrusion of vegetable proteins and the functionality of textured vegetable proteins (TVP). In the experimental work the research materials were faba bean protein concentrate and oat concentrate with high β-glucan content. The flour concentrates were texturized with high-moisture extrusion, in different mixtures. Mixtures were prepared in the ratio of: 3:1 (FO) and 1:3 (OF) and soy protein concentrate (S) was used as a reference sample. Moisture content and water absorption capability of TVP samples were measured instrumentally. TVPs were later on applied to develop burgers based on a mixture of meat and vegetable sources. Burgers were prepared for instrumental analysis with seven different recipes, where TVP inclusion, water addition and meat content varied. TVP was included in three different percentages: 0, 25 and 50% and water was added in 0, 12.5 and 25%. In relation to TVP inclusion and water addition, the meat content varied between 25-100%. Sample with 100% meat was used as control sample (0-sample) and burgers with S inclusion as reference samples. Samples were analyzed for cooking loss, shear force and texture profile (hardness, fracturability, springi-ness, cohesiveness, gumminess, chewiness and resilience) which was measured with a compression method. Based on the results of the instrumental analysis, five different burger samples were selected and evaluated for sensorial properties (chewiness, biting force, juiciness and pasty mouthfeel). The highest TVP moisture content was in OF and lowest in FO, hence the difference between S and FO was not significant. The highest water absorption was in S and lowest in OF. 25% TVP inclusion in burgers reduced the cooking loss (p<0.05) and 50% inclusion reduced it even more (p<0.05). With 25% TVP inclusion S had higher (p<0.05) cooking loss compared to FO and OF. With 50% TVP inclusion the difference was eliminated. Water addition increased cooking loss significantly (p<0.05) with each type of TVP. The FO and OF inclusion showed to weaken (p<0.05) the textural properties of burgers and reduced (p<0.05) the shear force. The reference sample S was found to maintain the structure similar as from the meat control sample. Water addition, while replacing meat, weakened also the textural properties and shear force in each TVP included sample. Based on the results, the inclusion of FO and OF in burgers reduces the cooking loss compared to the 0-sample and the reference sample S. The texture of burgers became weaker with FO and OF inclusion, however sensory evaluation revealed them to be similar to S included sample. Therefore additional studies focusing on improving the textural properties of these TVPs are needed. Faba bean and oat concentrates with higher protein contents could be needed to obtain a texture closer to meat.
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(2015)Tässä tutkielmassa selvitetään, kuinka venäläiset kuluttajat suhtautuvat funktionaalisiin elintarvikkeisiin. Funktionaaliset elintarvikkeet ovat Venäjällä verrattain uusi ilmiö ja kuluttajien asenteet tuotteita kohtaan yhä vakiintumattomia. Tutkimuksen kannalta keskeisiä aiheita ovat kuluttajien asenteet teknologisesti muokattuja elintarvikkeita kohtaan, elintarvikkeen terveysväitteen merkitys tuotteen lisäarvon muodostumisen kannalta sekä venäläisten kuluttajien yleinen suhtautuminen terveysväittämällä varustettuja elintarvikkeita kohtaan. Suhtautumista selvitettiin venäläisille kuluttajille suunnattuna internet-kyselynä. Tutkielman aineisto koostuu 159 vastauksesta, jotka analysoitiin tilastollisia työkaluja apuna käyttäen. Tutkimuksen tulosten perusteella voidaan todeta, että Venäjällä ollaan hyvin kiinnostuneita funktionaalisista elintarvikkeista, mutta käsite ”funktionaalinen elintarvike” ei ole kuluttajille juuri itsessään tuttu. Saatujen tulosten mukaan suurin osa kuluttajien funktionaalisiin elintarvikkeisiin liittyvistä epäilystä kohdistuu hyvin periaatteellisiin kysymyksiin, esimerkiksi uusi valmistusteknologia saattaa saada valintatilanteessa merkittävää painoarvoa. Funktionaalisten elintarvikkeiden omaksumisessa korostuu kuluttajan luottamus niin tieteelliseen tutkimukseen, tuotteiden valmistajiin kuin tuotteiden markkinoijiin. Tulosten mukaan kuluttajat harvemmin luottavat markkinointikampanjoihin, joten erityisesti asiantuntijoiden rooli tiedonvälittäjänä on tärkeä. Terveydenhuollon ammattilaisilla nähdään olevan olennainen rooli kuluttajien tietoisuuden kasvattamisessa Venäjällä, sillä elintarviketeollisuuden yritykset koetaan liian puolueellisina todenmukaisen informaation levittämiseen. Lisäksi tulokset osoittavat, että terveysväitteen nähdään tuovan tuotteelle lisäarvoa. Motivaatio tuotteen käytölle syntyy kuitenkin ainoastaan siinä tapauksessa, mikäli kuluttaja ymmärtää terveysväitteen ja tuotteen terveysvaikutus tuntuu itselle merkitykselliseltä. Venäjällä suomalaisia elintarvikkeita pidetään saatujen tulosten perusteella korkealaatuisina, ja tuotteen suomalainen alkuperä lisää kuluttajien luottamusta funktionaalisen elintarvikkeen toimivuuteen. Hyvin Suomessa menestyneet funktionaaliset elintarvikkeet luovat uskoa alaan kohdistuville suurille odotuksille, ja saadut tutkimustulokset lisäävät toivoa menestystarinoihin myös Venäjällä.
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(2021)Fusarium proliferatum has recently become a major threat to onion, which is an important food crop for food security and has a significant role in the agricultural sector. This fungus is found causing rots and producing mycotoxin fumonisin that, if ingested, can cause carcinogenic effects in humans and fatal diseases in animals. F. proliferatum has been identified as a pathogen causing rots and wilts in many plants in several countries, and recently some isolates of this pathogen were also found in Finland causing basal rot in onion. Though F. proliferatum has wide adaptability and pathogenicity, there are research gaps on this newly emerging pathogen, which is mostly limited to some specific hosts such as maize. There is a lack of knowledge of its infection mechanisms and mycotoxin production dynamics in onion. This experimental work was conducted at the University of Helsinki, Finland, to study the nature of pathogenicity and toxin gene expression of F. proliferatum in laboratory conditions as a function of time. Spore suspensions of three isolates of F. proliferatum, Fpr047, Fpr049, and Fpr919, were prepared and used as inoculums that were injected into healthy organically grown onions, which were then stored in dark for five weeks. Control bulbs were inoculated with sterile water. Pathogen virulence, based on symptom development, and fungal colonization in the onion tissues were determined at five different time points and the toxin gene expression was determined at three time points. Colonization levels were determined by real-time PCR using primers binding to the intergenic spacer (IGS) region of F. proliferatum. A part of the IGS region of the three isolates was sequenced to study the diversity between the isolates. All the tested isolates were found to be virulent, and they colonized the onions after one week from inoculation. However, the isolate Fpr919 appeared different from the other two in terms of symptom severity. It was more aggressive than the other two, causing disease symptoms earlier and causing more severe rot symptoms in the infected bulbs. It also had nucleotide sequence variations in the IGS region in comparison with the other two isolates, suggesting genetic diversity. No significant differences were observed between the isolates in the fungal colonization levels. Expression of FUM1 gene and a putative virulence gene SIX2-1 was detected by RT-RT-PCR in most of the infected tissue samples. The results obtained signify that F. proliferatum is a pathogen with the potential of producing fumonisin toxin in onion, suggesting the need for further molecular study on this fungus to control the disease and prevent mycotoxin contamination in plant products.
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(2018)Tieteen- ja politiikanaloilla on viime vuosina esiintynyt kasvavissa määrin mielenkiintoa biotaloustermiä kohtaan. Viime aikoina julkaistuihin poliittisiin dokumentteihin kuuluvat eri valtioiden ja kansainvälisten organisaatioiden kuten Euroopan unionin ja OECD:n biotalousstrategiat. Tähänastinen aiheeseen liittyvä tutkimus on keskittynyt lähinnä eri biotalousstrategioiden sisältöjen tutkimiseen. Lisäksi biotalouden määritelmään ja tulevaisuuteen liittyviä tutkimuksia erityisesti teknologisestä näkökulmasta on tehty jonkin verran. Tutkimuksia biotalouden sosiaalisesta puolesta, kuten sen eri sidosryhmien näkemyksistä biotalouden kehittymiseen ei sen sijaan ole juurikaan tehty. Biotalousstrategioiden onnistuneen toteutuksen varmistamiseksi on tärkeää, että eri sidosryhmät hyväksyvät biotalouskonseptin ja jakavat samansuuntaiset visiot sen tulevaisuudesta. Näin ollen on tärkeää ymmärtää miten eri toimijat käsittävät konseptin ja kuinka se mahdollisesti vaikuttaa heidän tuleviin toimiinsa. Tämä tutkimus auttaa hahmottamaan miten biotalouskonsepti ymmärretään Suomen kuitupohjaisella pakkaussektorilla ja millaisena eri sidosryhmät näkevät tulevaisuuden kehityksen. Tutkimus perustuu kirjallisuuskatsaukseen sekä laadulliseen analyysiin, jota varten on haastateltu 14:ää biotalouden asiantuntijaa. Tutkimus on ensimmäisiä laatuaan, joten sidosryhmät valittiin tarkoituksena kattaa sektori laajasti. Painotus asetettiin kuitenkin teollisuuden edustajille, jotta riittävä ymmärrys tulevaisuuden kehityspoluista liiketoiminnan näkökulmasta olisi mahdollista saavuttaa. Muita sidosryhmiä tutkimuksessa edustivat tutkimus, julkinen hallinto ja kansalaisjärjestöt. Tulokset osoittavat, että, sidosryhmien ymmärrys biotalouskonseptista oli samantapainen. Konseptin taloudelliset motiivit tunnistettiin tärkeäksi tekijäksi, vaikka myös ympäristöön liittyviä kestävyystekijöitä nostettiin laajasti esille. Keskityttäessä tarkemmin joihinkin aiheisiin, haastateltavien mielipiteet alkoivat erota toisistaan. Suurimmat erot hyväksyttävyydessä ja asenteissa löytyivät teollisuuden edustajien ryhmän sekä sen ja muiden sidosryhmien välillä. Teollisuuden edustajien näkemykset ulottuivat optimistisista näkemyksistä erittäin skeptisiin ja turhautuneisiin näkemyksiin biotaloudesta ja sitä kuvailtiinkin usein markkinointiterminä. Kuitenkin eri kestävyystekijöiden huomioiminen koettiin tulevaisuuden kilpailukykyä parantavana tekijänä. Muut sidosryhmät jakoivat positiivisen näkemyksen biotaloudesta sektoreita yhdistävänä konseptina. Tutkimus osoitti, että kaikki sidosryhmät on huomioitava biotalouskonseptin tulevaisuuden kehityksessä. Brändien omistajat koettiin kaikkein potentiaalisimmiksi muutoksen synnyttäjiksi, mutta heidän näkemykset puuttuivat tästä tutkimuksesta. Tutkimus keskittyi biotalouden operatiivisiin toimijoihin, jota voidaan pitää toisena tutkimusta rajoittavana tekijänä, koska se heikentää tutkimuksen luotettavuutta strategisesta näkökulmasta. Lisäksi osassa haastatteluissa ei päästy haastateltavan omien tarkoitusperien yli vaan haastattelut jäivät siltä osin pinnallisiksi, haastateltavien omia asemiaan suojeleviksi.
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(2010)Towards the year 2030 in Finland, sustainability issues will be dominated by climate change, the worsening state of the Baltic Sea, technological and technical development, globalization, the degradation of ecosystem services and increasing energy consumption. At the decision-making level, setting strategic objectives towards the year 2030 should consist of increasing energy efficiency, halting the reduction of biodiversity and changing consumption habits. Furthermore, promoting public transportation, limiting greenhouse gas emissions, increasing the proportion of renewable energy sources and linking climate policy to all sustainable development policies should be targeted in strategic long-term planning. This master’s thesis research was implemented as a Delphi study, a method commonly used in futures research. In a Delphi study the expertise of a chosen panel is utilized to gather information on a given topic. The research aimed at investigating the experts’ views on 1) the most important driving forces – changes and trends – affecting sustainable development towards the year 2030 2) the desirability and probability of different sustainability objectives and 3) recognizing the potential political conflicts brought by these strategies. The Delphi study was carried out during February 2010 – April 2010. It consisted of two rounds. The first round questionnaire was sent 43 experts (response rate 56 %). During the second round the most interesting first round results were completed with qualitative arguments (response rate 50 %). The results were analyzed in the manner that the research issues of most interest were 1) the trends having the most importance towards the year 2030 2) the most desirable strategic objectives with a high probability for political conflicts. The results indicate a high risk for political conflict especially with the targets on halting the reduction of biodiversity and changing consumption habits. These two objectives were considered difficult to grasp and often overruled by economic interests. Changing the current societal system based on continuous growth and consumption would require profound alterations in economy, society and individual values. The results also indicate that energy is a key issue for the coming decades: setting strategic objectives for replacing fossil fuels should be among the top priorities of the Finnish national government. Also, in addition for climate change being an important trend, the deviation of rankings in importance among the panel indicated a possibility for social and economic trends to have unexpected, sudden effects as we move towards the year 2030. These include global poverty and inequality, changing age structures and the sustainability of the Finnish economy.
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(2015)The scope of the literature review was to define the physical properties and crystallization of amorphous sugars as single substances and mixtures. The purpose of the experimental part was to measure the water sorption, glass transition and crystallization of sucrose, isomaltulose and different mixtures of both. Crystallization and water sorption was measured with Dynamic Vapour Sorptions (DVS) -system, and with a differential scanningcalorimeter (DSC). Water sorption was studied by weighing samples that were stored at different relative humidities (11 - 85 %). Crystal forms were studied with the x-ray diffraction method. The sucrose samples reached a stable-state at relative humidities of 11-33% in one day of storage. The same was true for isomaltulose samples. Mixtures adsorbed more water the higher the relative humidity. Mixture samples reached a stable state in a day of storage at relative humidities of 11 - 44 %. Water sorption was modelled with the BET-model. The glass transition temperature, measured with DSC, of anhydrous sucrose was measured at 57 ºC. The glass transition temperature of anhydrous isomaltulose was slightly lower 47 ºC. The glass tranition temperature of a mixture sample, at 0 % relative humidity, was in between those two, 50 ºC. The glass transition temperature of sucrose was higher than that of isomaltulose after storage at relative humidities of 11 - 33 %. The critical water content of sucrose and mixture was 3, for isomaltulose it was 2 (g water/100 g solid). The critical storage humidity for sucrose was 25 %, for isomaltulose and mixtures it was 20 %. In testing with DSC sucrose was the only sample to crystallize. The higher the storage relative humidity before testing, the lower the crystallization temperature was for all sucrose samples. Crystallization temperature test run with the DVS system showed that sucrose crystallized at lower relative humidity than a mixture. Pure sucrose and mixtures did not share any reflection angles in x-ray diffraction tests, but isomaltulose and mixtures shared many reflection angles. This led to the conclusion that the mixtures contain more isomaltulose crystals than sucrose crystals. Adding isomaltulose to sucrose did not have a large effect on glass transition temperatures. Glass transition temperatures for mixtures were inbetween sucrose and isomaltulose. Isomaltulose however retarded crystallization greatly. The mixture required a significantly higher relative humidity in order to crystallize than either sucrose or isomaltulose.
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(2023)Täsmäviljelyn yleistyminen on lisännyt tarvetta maaperän spatiaalisen vaihtelun kartoittamiselle, ja tämän myötä markkinoille on tullut erilaisia maaperäkartoitusmenetelmiä. Tämän tutkimuksen tavoitteena oli selvittää, pystytäänkö gammasäteilyn mittaamiseen perustuvalla SoilOptix-maaperäkartoitusmenetelmällä estimoida pellon sisäistä pH-arvon, helppoliukoisen fosforin sekä mangaanin vaihtelua. Tutkimus toteutettiin Forssassa sijaitsevalla peltolohkolla, jossa yhteensä 48 mittauspisteen maa-analyysituloksista ja SoilOptix-menetelmän pistemäisistä estimaateista tehtiin korrelaatioanalyysejä ja pistekaavioita. Myös gammasäteilyraakadatan toistettavuutta havainnoitiin visuaalisesti. Työn toinen tavoite oli selvittää, vähensikö peltolohkolle tehty täsmäkalkitus pellon sisäistä satovaihtelua ja ravinnevaihtelua. Tämän selvittämiseksi analysoitiin puimurin satokartoitusaineistoja vuoden 2020 kevätrapsin (Brassica napus ssp. oleifera (Moench) Metzg.) ja vuoden 2022 kevätvehnän (Triticum aestivum L.) puinneista. SoilOptix-menetelmällä ei pystytty estimoida peltolohkon sisäistä vaihtelua minkään koejäsenen osalta. Kalkitus ei oleellisesti vähentänyt peltolohkon sisäistä satovaihtelua, mutta ravinnevaihtelua se vähensi. Eri vuosien gammasäteilyn raakadatassa oli samankaltaisuuksia visuaaliseen havainnointiin pohjautuen. Syyt heikkojen korrelaatioiden taustalla eivät ole ilmeiset, ja ne vaatisivat lisätutkimusta. Erityinen kiinnostuksen kohde olisi menetelmässä kerätyn raakadatan lukuarvot, joita ei tässä tutkimuksessa saatu tarkastella. Johtopäätöksenä todetaan selvä lisätutkimuksen tarve menetelmälle.
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(2018)The Khwe San, the residents of Bwabwata National Park (BNP), were hunter-gatherers who used to acquire their food by hunting and collecting veld food in the past. However, they are not allowed to practice their traditional methods anymore due to the status of the park as a national park and the army trying to prevent increased poaching in the bush. Nowadays they are highly dependent on food aid provided by the Namibian government. In addition, small-scale subsistence agriculture is practiced but due to drought and wild animals, harvests are insufficient to meet required food demand on a daily basis. The objective of this research was to investigate gardening opportunities of the Khwe San in the Eastern part of BNP. The data were collected through semi-structured interviews with 38 respondents and several stakeholders. Four different groups were found which were home gardeners, community gardeners, participants of gardening workshop and non-gardeners. The data were analysed using a thematic content analysis, a SPPS statistic programme and a sustainable rural livelihoods framework. In addition, one positive deviance gardener was selected, and his production methods is described in more detail. The main results highlighted the importance of having gardens. All the respondents indicated that gardening is important or very important in terms of food production and income generation. However, the majority of the residents are willing to have home gardens due to the challenges of community gardens in the past e.g. the lack of cooperation, jealousy and stealing as well as the lack of needed goods. Current challenges are that there are only one or two water sources in each village and the distances from the boreholes to gardens are long, which complicates irrigation. In addition, poor fences and lack of seeds and tools are the major challenges that home gardeners face. Future training should include specific things because the interviews showed that the general gardening knowledge is presented. As a conclusion, the focus of gardening should be on home gardens, not on community gardens due to their challenges. However, in order to make gardening sustainable, several activities need to be addressed, including an active agriculture extension officer for monitoring, training on specific things and seed distribution provided by the government. In addition, the gardening support needs to be aimed to dedicated people who are willing to practice gardening
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(2018)Syftet med avhandlingen var att med statistiska metoder utreda ifall, och i så fall hur och hur kraftigt LIR-gårdarnas gårdsarealer påverkar dess lönsamhet. I den första delen undersöktes hur gårdens nettovinst per hektar i medeltal påverkas av gårdsarealen. I den andra delen undersöktes hur styckkostnaden för vårvete, maltkorn, vårraps och havre påverkas av gårdsarealen. Dessutom jämfördes gårdsarealens påverkan på lönsamheten med andra variablers påverkan för att ge proportioner åt fenomenet. Enligt teorin om stordriftsfördelar skulle styckkostnaderna sjunka till följd av att företagets storlek växer. Vid en viss storlek har alla fördelar utnyttjats och styckkostnaden börjar stiga igen då företaget växer ytterligare. Kurvan som beskriver styckkostnaden i förhållande till företagets storlek kallas för LRAC-kurvan och vanligtvis antar den en U- eller L-form beroende på hurudana stordriftsfördelar det finns att utnyttja. Materialet bestod av LIR-gårdarnas ekonomiska resultat för åren 2006 till och med 2015. LIR står för lantbrukssällskapets individuella rådgivning och är en rådgivartjänst som erbjuds av Nylands svenska lantbrukssällskap åt växtodlingsgårdar i Nyland. Det totala antalet observationer var 602. Metoden som användes var multipel linjär regressionsanalys. Som estimator användes OLS och WLS. Med hjälp av denna metod estimerades modeller som förklarade nettovinsten per hektar och styckkostnaden för tidigare nämnda grödor med bl.a. gårdsarealen som oberoende variabel. Regressionsanalyserna erhöll relativt höga förklaringsgrader. Den L-formade LRAC-kurvan visade sig passa bäst för det undersökta materialet. Gårdsarealen hade en signifikant inverkan på den beroende variabelns variation i fyra regressionsanalyser av fem. De andra variablerna förutom gårdsarealen som ingick i regressionsmodellerna verkade också signifikant påverka den beroende variabeln. Sammanfattningsvis innebär undersökningens resultat att gårdsarealen inverkar signifikant positivt på lönsamheten. Det förekommer inte heller starka antydningar om att det förekommer stordriftsnackdelar på de undersökta gårdarna. Däremot verkar odlingsgrödan göra skillnad ifall det finns stordriftsfördelar att utnyttja eller inte. Det kunde också konstateras att andra variabler har en större betydelse för lönsamheten än vad gårdsarealen har.
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(2020)The sequencing methods used to study the genome of organisms have become cheaper, resulting in a significant increase in the amount of genomic data available. Knowing the nucleic acid sequence of the DNA does not tell much about an organism. Not without first annotating the genome, which means searching for the locations of genes and defining their products. The programs used for annotation make mistakes and their results must be evaluated in various ways. The vast amount of genomic data encourages fast production of new annotations and this can increase human made errors. Some annotation programs use gene databases, so the number of wrongly annotated genes they contain may increase in the future if the quality control of annotations is not improved. This study examines correlation between selected quality measures and the quality of annotations. The quality metrics used can be divided into two basic types, the first one is based on the basic structures of genes and the second one on comparing the protein product of a gene against a protein database. The study assumes that comparison to a reference is a reliable way to assess the quality of annotations. The comparison is made at genome, exon and nucleotide levels. A single value describing the comparison is calculated at each level. For each gene aligned with a reference gene, sensitivity and specificity are calculated and used to make f-score at the nucleotide level. Four different versions of the wild strawberry (Fragaria vesca) genome and their six annotations were used as data. They were downloaded from the Genome Database for Rosacaea, which is a genome database specializing in rose plants. The correlation coefficients calculated from quality metrics and f-scores were in several cases small but reliable because the p-value was minimal. Correlation coefficients were higher when quality metrics based on protein homology were examined. The correlation coefficient calculated from the mean of the structure-based quality metrics and the f-score received lower values if the studied annotation had a high f-score value. These results detailed in this paper support the view that the selected structure-based quality metrics are not suitable for evaluation of high-grade annotations. They might possibly be used in automated detection of poor-quality annotations. Quality metrics based on protein homology appeared to be promising subjects for further research.
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(2020)Usp45 is the major secreted protein in Lactococcus lactis. Protein’s 27-aa signal peptide (SPUsp45) is widely used for increased secretion and improved yields of heterologous proteins. L. lactis, previously used mainly in food production, has gained increasing popularity in gene technology and, thanks to extensive research, became a Gram-positive model organism alongside Bacillus subtilis. Despite the widespread use of its signal peptide, the biological role of Usp45 protein remains largely a mystery. The aim of this study was to test whether decreased translation of the naturally highly secreted Usp45 protein would lead to improved secretion of desired heterologous proteins. The hypothesis was that high levels of secreted Usp45 cause the Sec translocon becoming a bottleneck and by reducing this strain on the secretion route, the capacity to secrete other proteins could increase. Based on literature, usp45 is not part of the L. lactis core genome and was assumed to be non-vital. To study this, the L. lactis strain NZ9000 was transformed with the plasmid pLEB805 which contains a nisin inducible antisense-usp45 gene (ASusp45) resulting in strain LAC455. The effect of antisense-RNA mediated silencing on growth and morphology of the cells was observed as well as the changes in quantity and quality of secreted proteins in ASusp45 induced cells. The secretion of heterologous proteins was tested with bacteriocins leucocin A and C that were introduced to the cells in expression vectors. This study brought new information on the function of the usp45 gene in L. lactis. The results show that the silencing of the usp45 gene leads to retarded growth rate, multifold ingrowth of the cell wall, aggregation of the cells and the leakage of cytoplasmic proteins leading to loss of viability of the cells. These results demonstrate that Usp45 is vital for the structure of the cell wall, cell separation and normal chain formation, and it probably acts as a vital peptidoglycan hydrolase.
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(2018)Cereal β-glucan, or (1→3)(1→4)-β-D-glucan, has unique viscous and gelling properties, which are related to its physiological effects. The increased viscosity in human gastrointestinal tract by β-glucan is considered a key factor for its health benefits. However, the possible gelling ability of β-glucan in human intestine and its relation to the physiological functionality have not been investigated. The aims of this study were to investigate the possible structure formation of β-glucan at physiological conditions and to understand gelation difference between oat and barley β-glucan (OBG and BBG, respectively). Additionally, the effects of phytate and molecular weight (MW) on structure formation of β-glucan were studied. Oat (ROBG14, ROBG22) and barley bran concentrates (RBBG18) were used for in vitro studies in upper gut model. OBG14 was extracted from oat concentrates and used for further producing phytate-removed OBG (PR-OBG) or enzymatically degraded OBG (ENZ-OBG). The effect of phytate or molecular weight on gelation of beta-glucan was studied by comparing the gelation of PR-OBG or ENZ-OBG to OBG14 after 2 h and 1 d. The effect of β-glucan source was studied with medium viscosity oat (MOBG) and barley (MBBG) β-glucan with same molecular weight and concentration on day 1 and day 4. The extracted samples were first dissolved at physiological T 37°C for 2 h and the gel properties of the samples were measured with oscillatory measurements. OBG showed more structure formation than BBG at low concentrations in both studies with in vitro digestion model and extracted β-glucan samples at physiological temperature. In vitro RBBG18 (β-glucan content of the in vitro extract 0.6%) showed liquid-like behavior and no hysteresis obtained, indicating no structure formation. ROBG14 (β-glucan content 0.5%) and ROBG22 (β-glucan content 0.6%) showed entangled network, with similar crossover frequencies, 0.07 and 0.1 Hz, respectively. 1.5% MOBG showed liquid-like behavior on day 1, but storage modulus (G’) increased during storage. The undissolved particles in watery medium of MBBG indicated 37°C was not enough for partial dissolution which could lead to gel. At the same concentration (1%), both PR-OBG and OBG14 showed weak gel structure, with slightly higher G’ in PR-OBG. This indicated that phytate is not the reason for better gelation of OBG than BBG, which was hypothesized due to higher residual phytate in OBG than BBG. ENZ-OBG (0.7%) had lower G’ than OBG14 (0.7%), which indicated more structure formed in higher MW OBG at 2 h. To conclude, OBG is more prone to structure formation than BBG at physiological conditions. Phytate was not the reason for better gelation of OBG than BBG.
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(2023)The current trend in the food and forest industries is to utilize sustainable and renewable products. One such product is galactoglucomannans (GGM), water-soluble hemicelluloses covering 25–35 % of the dry wood mass. GGM can be extracted from spruce sawdust or branches using a safe and environmentally friendly pressurized hot water extraction (PHWE) method. Deacetylation of GGM happening during extraction and concentration by membrane filtration at alkali conditions possibly enables gel formation. This thesis aims to observe if low acetyl GGM has the ability to form a gel and which factors have an impact on its gelation and gel properties. Low acetyl PHWE GGM powders were provided by the Natural Resources Institute of Finland (Luke). The GGM solutions at different pH values (4, 7, and 10) and solid concentration levels (5, 10, and 15 %) were prepared using a magnetic stirring rod and then ultrasonicated (50% amplitudes for 5 min). Viscosity, rheological properties, water holding capacity (WHC), hardness, and adhesiveness were measured on days 1, 2, 3, and 5 during storage at room temperature (22 °C). The results showed that GGM was able to form a gel at all investigated conditions, except for the samples at pH 4 and a solid concentration of 5 %. GGM solutions at high pH (7–10) and solid concentrations (10–15%) formed gels without ultrasonication. All GGM gels had high WHC (≥ 90 %). Gel viscosity increased with prolonging of storage time and increased solid concentration. The frequency sweep analyses showed that all investigated samples had a gel-like behavior. Gel hardness and adhesiveness increased in all the samples during storage and increased solid concentration. The thesis demonstrated that low acetyl GGM could form a gel, which could be used as a gelling agent, where solid concentration and pH impacted to gel structure. Thus, the study could widen industrial applications of GGM or at least engage interest.
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(2012)The literature review describes the characteristics, uses and probiotic potential of propionibacteria and gives an overview of proteomic methods focusing on 2-DE studies related to probiotic bacteria and P. freudenreichii. The aim of the experimental part was to use 2-DE to obtain proteome maps of two strains of P. freudenreichii and detect inter-strain differential protein expression. The influence of a number of parameters on the quality of 2-D gels was also investigated. The pH 3-7 and pH 3-11 NL proteome maps obtained displayed 305 and 356 spots, respectively, and detected the differential expression of 60 and 72 spots, respectively. The 3-11 NL proteome map showed spot over-crowding in the pH 4-6 region. Addition of 50 mM dithiothreitol (DTT) to the samples prior to isoelectric focusing (IEF) and an increase of IPG buffer concentration greatly improved spot resolution. Silver staining achieved higher spot counts than Coomassie staining. The influence of the number of lysis cycles on protein extraction was marginal, while lower protein sample loads produced superior 2-D gels. Results show that data from 2-DE proteome maps can provide an overview of inter-strain differential protein expression in P. freudenreichii. The optimal 2-DE experimental setup would include pH 4-7 IPG strips, a low protein load and inclusion of DTT in the IEF sample, as well as silver staining for spot visualisation.
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(2017)Gender diversity in the workforce describes the equal representation of men and women in terms of ratio. Raising importance of the concept due to changing societal norms has allowed researchers to explore the mostly positive effect gender diversity, especially in leadership level, has on a company’s performance. Despite all the benefits, women in the forest-based sector are still underrepresented. This study aims to understand the underlying reasons for female underrepresentation in the forestry sector and to identify solutions to improve the situation. The study explored the barriers and enablers that hindered or supported female career development in the forestry industry and investigated possible solutions in light of sector’s future goals. In-depth elite interviewing was selected as the method of data collection. Ten interviews with senior level female leaders of seven forestry companies in Finland and Sweden were conducted face-to-face or over the phone. The qualitative content analysis of data identified most common barriers faced by women in their careers: a) discrimination, exclusion, and stereotyping due to masculine company culture, b) balancing work and family due to inflexible working hours and lack of remote work possibilities. Moreover, it recognised the importance of competence development and support systems as the enabling aspects of women careers in the industry. In addition to further understanding gender effect in the forestry sector, the study allowed to look into the future of the sector through the eyes of female leaders. The findings of the study are in line with previous research that identified the career advancement barriers and enablers in other industries. However, culture-specific issues posing a challenge to female career development and promoting exclusion, such as sauna and hunting traditions, were identified. Additionally, the importance of a personal support system was highlighted in the study. The critical role of the forestry sector and the bioeconomy in the sustainable global future was recognised by all study participants. The ability of forestry companies to adapt to future needs and to become a part of modern society will require them to rethink old concepts, modernise the image and allow for a more diverse company culture to foster in all organisational levels.
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(2007)Virusinduced gene silencing (VIGS) vectors based on tobacco rattle virus (TRV) are now widely used for characterizing the function of plant genes. However, previous TRV vectors using RNA2 to carry the targeted gene sequence had difficulties to induce gene silencing on some plant species (Gerbera hybrida etc.) due to the obstacle of RNA2 movement. To achieve efficient gene silencing in those species, it is necessary to develop new TRV vectors, in which the targeted gene will be included in TRV RNA1 and the 16K gene will be replaced. Based on TRV RNA1, two new VIGS vectors M1 and M2 were developed through deletion part of 16K gene. Another mutant 16Kstop was also constructed to carry an early terminator in the 4th codon of 16K gene. The infectivity and gene silencing efficiency of the new constructs were assessed through a series of infection experiments. It was found that the infectivity of M1 and M2 was lower than wild TRV RNA1. M1 and M2 could induce PDS gene silencing on Nicotiana benthamiana, but their gene silencing efficiency was limited as compared with previous TRV VIGS vectors in which the PDS gene fragment was contained in RNA2. We also found that the 16K gene sequence, rather than the 16K protein, was required for efficient virus movement and accumulation.
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(2019)Mycosporines and mycosporine-like amino acids (MAAs) are small-molecules that provide UV protection in a broad range of organisms. Cyanobacteria produce a diverse set of MAA chemical variants, many of which are glycosylated. Even though the biosynthetic pathway for the production of a common cyanobacterial MAA, shinorine, is known, the biosynthetic origins of the glycosylated variants remains unclear. In this work, bioinformatics analyses were performed to catalogue the genetic diversity encoded in the MAA gene clusters in cyanobacterial genomes and identify a set of enzymes that might be involved in MAA biosynthesis. A total of 211 cyanobacterial genomes were found to contain the MAA gene cluster, with six containing glycosyltransferase genes within the gene cluster. Afterwards, 38 strains from the University of Helsinki Culture Collection were tested for the production of MAAs using QTOF-LC/MS analyses. This resulted in the identification of several novel glycosylated MAA chemical variants from Nostoc sp. UHCC 0302, which contained a 7.4 kb MAA biosynthetic gene cluster consisting of 7 genes, including two for glycosyltransferases and one for dioxygenase. Heterologous expression of this gene cluster in Escherichia coli TOP10 resulted in the production of a glycosylated porphyra-334 variant of 509 m/z by the transformant cells, showing that colanic acid biosynthesis glycosyltransferases can catalyse the addition of hexose to MAAs. These results suggested a biosynthetic route for the production of glycosylated MAAs in cyanobacteria and allowed to propose a putative role for dioxygenases in MAA biosynthesis. Further characterization of additional glycosyltransferases is necessary to improve our understanding of glycosylated MAA biosynthesis and functionality, which could be applied to large scale processes and be used in industrial applications.
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(2012)Class IIa (pediocin-like) bacteriocins are a major group of bacteriocins produced by lactic acid bacteria (LAB) characterised by their antilisterial activity. As a protective LAB strain for meat products, Leuconostoc carnosum 4010 kills Listeria by producing two class IIa bacteriocins, the well characterised leucocin A (LeuA) and the less studied leucocin C (LecC). Although the amino acid sequence of the secreted LecC has been published, the genes required for its production remain unknown. The aims of this study were to characterise the genes needed for LecC production and to express the lecC gene in Lactococcus lactis. The lecC gene was localised by Southern blot in a large plasmid different from the one harbouring LeuA genes in Ln. carnosum 4010 genome. Five genes in two operons were identified mainly by PCR-based methods and sequencing, namely, the structural gene (lecC) with a 72-bp signal sequence, the immunity gene (lecI) encoding a 97-aa immunity protein, two genes lecTS for an ABC transporter and the gene lecX for an accessory protein. The immunity function of LecI was demonstrated by expressing the lecI gene in LecC sensitive Listeria monocytogenes. Compared to the wild type, LecI-producing Listeria was more tolerant to LecC, thus corroborating the immunity function of LecI. For heterologous expression of LecC, the lecC gene was fused to the lactococcal usp45 signal sequence in the nisin-selectable and nisin-inducible food-grade secretion vector pLEB690. Consequently, bioactive LecC was secreted efficiently by the recombinant Lc. lactis. In conclusion, novel genes for the production of LecC in Ln. carnosum 4010 were identified. The findings indicate that LecC is produced by a dedicated system independent of LeuA. The successful production of functional LecC in Lc. lactis offers an attractive approach for the future application of bacteriocins in food production.
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(2009)Genetic composition of Theobroma cacao L., including 60 Nicaraguan farmers accessions, was investigated using nine microsatellite (SSR) markers. Fourteen breeders accessions from Experimental Center “El Recreo”, INTA, Nicaragua, two Criollos accession from CATIE, Costa Rica, and two accessions from Ecuador were included as reference material. The average PIC value (0.78) indicated a high power of discrimination for the nine loci used. A total of 155 alleles were detected at the nine loci. The number of alleles per marker ranged from 10 to 22 with a means of 17.22 alleles per locus. A heterozygosity deficiency (HExp < HObs) was registered for all microsatellite loci. The average expected heterozygosity was=0.68 among Nicaraguan farmers accessions. The Analysis of molecular variance (AMOVA) showed a low level of differentiation among populations. The genetic distances determined for the groups of farmers accessions RAAS and Pacifico Sur are closely similar, while a great genetic distance was observed between RAAN and RAAS groups. The cluster analysis presented a strong genetic relation between the Criollo 13 from CATIE and farmers accession MAT0404. The principal component analysis showed that 7 farmers accession from Nicaragua are genetically related with the accessions Criollo 13 and Yucatan from the international accessions. The present study suggested a good possibility to select farmers accessions to be included in breeding programs, especially those accessions related to know Criollo accessions.
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(2009)Strawberry (Fragaria × ananassa) is the most important berry crop cultivated in Finland. Due to the species' economic importance, there is a national breeding programme aimed at extending the cropping season from the current one month to up to three months. This could be achieved by growing cultivars which would initiate flowers throughout the summer months, without the requirement of a period of short days as is the case with currently grown cultivars. The cultivated strawberry is an octoploid and therefore has complex patterns of inheritance. It is desirable to study the genetic mechanisms of flowering in the closely related but diploid species F. vesca (L). In the diploid Fragaria, a mutation in a single locus, namely the SEASONAL FLOWERING LOCUS (Sfl), changes the flowering phenotype from seasonal to perpetual flowering. There is also an array of genetic tools available for F. vesca, which facilitate genetic studies at molecular level. Experiments described here aimed at elucidating the identity of the gene which confers perpetual flowering in F. vesca by exploring the flowering characteristics and genotypes of five F2 populations (crosses between seasonal × perpetual flowering cultivars). The study took advantage of a genetic map for diploid Fragaria, publicly available EST and genomic Fragaria sequences and a recently developed BAC library. Sequence information was used for designing gene–specific primers for a host of flowering–related candidate genes, which were subsequently mapped on the diploid Fragaria genetic map. BAC library was screened with molecular markers supposedly located close to the Sfl, with the aim of positionally cloning the Sfl. Segregation of flowering phenotypes in the five F2 populations showed, that the Sfl indeed controls flowering in all the tested cultivars. A genetic map was constructed of the chromosome with the Sfl, and a positional cloning attempt was initiated with the closest flanking markers. 45 gene–specific primers pairs were designed for 21 flowering–related genes, and eight genes were successfully mapped on the diploid Fragaria map. One of the mapped genes, namely PRR7, located very close to the Sfl, and is a potential candidate for the gene that has evaded identification so far.
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